gtk-Fehlermeldungen

Liebe Freunde!

In meinem gtk-1.2- Programm (Ein Terminal für 
Amateurfunk-Digimode) funktionieren die unten zitierte  
Funktion und einige andere, ähnliche,  gut. 

Aber die Fehlermeldungen
gefallen mir nicht und ich möchte sie ergründen und 
beseitigen - weiß jemand Rat?

 ################################################
Funktion:

void display_status(const char *fmt, ...){
	GtkText *txt;
	unsigned int len;
        va_list args;
	char display[256];

	if (!fmt || !(len = strlen(fmt)))
		return;
	
	memset (display, 0, sizeof(display));
	
txt=GTK_TEXT(gtk_object_get_data(GTK_OBJECT(wmain),"textstatus"));
	// to prevent stack overflow while running loooooong
	while (gtk_text_get_length(txt) > MAXMON)
	{
	 gtk_text_freeze(txt);
	  gtk_text_set_point (txt, 0);
	  gtk_text_forward_delete (txt, MAXMON / 2);
	  gtk_text_set_point (txt, gtk_text_get_length(txt));
	 gtk_text_thaw(txt);
	}
        va_start(args, fmt);
	vsnprintf(display, sizeof(display), fmt, args);	
        va_end(args);
	gtk_text_insert(txt, NULL, NULL, NULL, display, 
strlen(display));
	gtk_text_insert(txt, NULL, NULL, NULL, "\n", 2);
}

#############################################
Fehler: 

Gtk-WARNING **: invalid cast from (NULL) pointer to 
`GtkObject'

Gtk-CRITICAL **: file gtkobject.c: line 1079 
(gtk_object_get_data): assertion `object != NULL' failed.

Gtk-WARNING **: invalid cast from (NULL) pointer to 
`GtkText'

Gtk-CRITICAL **: file gtktext.c: line 905 
(gtk_text_get_length): assertion `text != NULL' failed.

Gtk-CRITICAL **: file gtktext.c: line 953 (gtk_text_insert): 
assertion `text != NULL' failed.

Gtk-CRITICAL **: file gtktext.c: line 953 (gtk_text_insert): 
assertion `text != NULL' failed.

Gtk-WARNING **: invalid cast from (NULL) pointer to 
`GtkObject'

###############################################
Danke !!!!
-- 
Günther Montag
[email protected]



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